The earliest I can recall watching F1 was snippets of it in the early 2000s on Speedvision, with the only F1 driver I heard of at the time being Schumacher. Being an amateur history buff, including motorsport history, I felt compelled to research more since I began watching/following in 2014, and mainly on a part-time basis, which was also when Hamilton started winning again and again for Mercedes. Bad timing, I know. Ergo, don't take this as an expert opinion, please.
Do I believe Hamilton is a skilled driver? Yes. No question. Do I think he is GOAT right now? Seriously? The answer is the same as to him getting his apparent knighthood. Way too soon. Those who want to knight him seriously should have waited until he retired completely from motorsport period. Since I don't live in the UK, I can't claim any knowledge on how to qualify for such an honor, but I firmly believe one such qualification should be that the recipient's career, be it in sport, entertainment, politics, etc., should be over (underline for emphasis). The main reason I can see, without doing much research, for his knighthood is ideological. Which brings me to my next point. Over the past couple of years, I've grown annoyed by his off-track actions and viewpoints in addition to his over-aged childish behavior. This past year he's dragged his beliefs with him to the track, which like most entertainment venues anywhere, should be neutral ground; a place for all people of all walks of life and viewpoints. He may not intend this to happen, but when people like him express his politics during an event and even go far enough to try and force others to agree with him, it's akin to him saying he wants to lose fans and so should the sport.
GOAT candidates in any sport should not be forcing fans to leave that sport. Period. They should be doing their darnedest to keep them at least in the sport.
Finally, I don't necessarily think he's winning the way he is just because he has great equipment with Mercedes. Time and time again this past season we've all seen in one instance or another what the sport can be like without him as a factor. An F1 without Hamilton as a competitor/dominator has proven to be entertaining, if not a truthful revelation of the skills of the rest of the grid. It's as if his absence turned off a restrictive switch habitually built in to the minds of everyone else. There are great and potentially great drivers out there on the grid and waiting in the wings. I think a good chunk of the problem is with the other teams. As a part-time Ferrari fan, it pains me to say that team is now struggling to find how to win without cheating (intentionally or otherwise), and having a history of lions being led by deer (see the Theodore Roosevelt quote if you don't understand the reference). Mclaren can't find a proper engine supplier or keep good drivers. Red Bull, the closest Mercedes has to rivals, is too much like them in one respect: they both have a great lead driver, but both are also having a hard time keeping a number two driver. The key difference is Mercedes doesn't have to worry about engine suppliers, as opposed to Red Bull. Racing Point/Aston Martin threw away a good driver because he has the wrong last name and a smaller wallet, in addition to an aerodynamics department with no imagination. The others are more concerned with being junior teams trying to score one point per event and finding the best place to farm out their drivers to. I may be wrong, but the FIA has gone after Mercedes a few times for violating the rules, so I don't think we can claim Ferrari-Todt style bias by them towards Mercedes.
In short, it's easy for one to be greatest of his respective era when it seems the competition has, with the exception of one Mad Max Verstappen, given up trying to win event after event and just got content with less because of one driver.
So with Hamilton being the best of the 2010s by default only, I think that it must be said that Schumacher was the best of the 2000s, Senna and then Hakinnen being the best of the '90s, and so forth. To each era, their own, and please leave it as such.